When gold was new to American investors in the 1970s, the South African Krugerrand was advertised as the world's best way to own gold.

The U.S. Mint might adopt a slogan for its gold coins, "the best that money can't buy."

Word came yesterday that the proof 2007 Buffalo one-ounce coins were taken off the market for an indefinite period to allow the Mint to reprice.

This is becoming a routine. Sept. 13 the Mint took the "W" uncirculated gold American Eagle coins off the market for what was initially hoped as a two-week period that has now turned into nearly a month.

New "W" unc. prices will be published in the Federal Register tomorrow, clearing the way to put them back on the market. I don't know how much time will elapse between publication and return. Keep an eye on the Mint's Web site.

With so much interest in gold at the moment, the Mint's predicament is unfortunate. I don't expect the Mint to sell at a loss to current market value, but I have commented that the pricing mechanism is obviously more unwieldy than it should be if it takes such a long time to get the coins back on the market.

Some readers have e-mailed me that the Mint should just go on selling, much as they are striking nickels and putting them into circulation at a loss.

That is contrary to all business logic and I don't expect it. It is a bit surprising that there is some sense of entitlement to buy coins at yesterday's prices knowing that gold has gone up since.

I don't know yet how long the proof Buffalo coins will be off sale. The September precedent isn't promising, though.

About the Author David C. Harper has been a coin collector since 1963. He joined the Krause Publications editorial staff in 1978 and is currently editor of Numismatic News and World Coin News. He also edits two books annually, North American Coins & Prices and Coin Digest. He is the author of the Class of '63 column that runs each week in Numismatic News. His first bylined numismatic article appeared in the June 1971 issue of Coins Magazine and his various Krause Publications assignments included a stint as editor of the magazine 1980-1983. Harper received a bachelor of science degree from the University of Wisconsin-Oshkosh in 1977. He had a double major of journalism and economics.